• 제목/요약/키워드: Information Priority

검색결과 2,383건 처리시간 0.029초

Total Resource Requirements-Based Priority Queuing Scheme for DS/CDMA Cellular Networks

  • Piao, Shiquan;Park, Jae-Won;Park, Yong-Wan
    • ETRI Journal
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    • 제28권3호
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    • pp.371-374
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    • 2006
  • We propose and analyze a priority queuing scheme that gives priority in the same class of calls according to their total resource requirements (TRRs). The proposed scheme gives a higher priority to the calls that have a lower TRR over the calls that have a higher TRR. The numerical results show that the proposed priority queuing scheme provides better performance than the traditional queuing schemes in call blocking probability.

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대중교통 HUD 콘텐츠 우선순위 결정에 관한 연구 (The Decision of Order Priority of HUD Contents for Public Transit)

  • 박범진;강원의;김태형
    • 한국도로학회논문집
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    • 제15권1호
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    • pp.135-141
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    • 2013
  • PURPOSES: In this study, as part of an effort to develop HUD for public transit, it is proposed that the decision of order priority of contents which will be disposed to bus drivers through HUD for public transit using AHP(Analytic Hierarchy Process) technique. METHODS: In AHP analysis method brainstorming, factor analysis, hierarchical structuring, and weighting analysis were performed by applying a classical analysis method. RESULTS: By the result of analysis it is shown that unlike car drivers, bus drivers prefer information related to bus intervals, bus stop, and door open and close to information related to vehicle running. Also, bus stop information and bus interval information were ranked as first and second place in order priority of HUD contents for public transit by experts. CONCLUSIONS: This method of selecting order priority of HUD contents for public transit can provide a basic foundation for selecting order priority of traffic information contents as well as other HUD contents.

A Priority Scheme for IEEE 802.11 Wireless LAN

  • Jang, Yeong-Min
    • 한국통신학회논문지
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    • 제25권12B호
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    • pp.1996-2002
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    • 2000
  • This paper investigates a priority scheme for IEEE 802.11 Carrier Sense Multiple Access/Collision Avoidance (CSMA/CA) protocol in order to provide short access times for priority frames (e.g. time-deadline traffic) even when the overall traffic on the wireless channel is heavy. Under the compatibility constraint for the IEEE 802.11 wireless LANs, two priority systems are simulated: no priority (current IEEE 802.11 standard) for time-deadline traffics and dynamic time-deadline priority. We evaluate algorithms to improve the time-deadline traffic performance using discrete event simulation (DES)

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Maximum User Utility on Contents Delivery System with Multiple Priority Classes

  • Yamori, Kyoko;Tanaka, Yoshiaki;Akimaru, Haruo
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2002년도 ITC-CSCC -2
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    • pp.1113-1116
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    • 2002
  • For contents delivery systems, the service is considered in which the utility depends on each priority class. This paper deals with the multiple priority class of the contents delivery system from the viewpoint of the utility. The willingness to pay (WTP) is introduced as a measure of utility, and the optimum condition is analyzed to maximize the total user's utility. For the system with multiple priority classes, the optimum condition is given in terms of the traffic load, wating time for service for each priority class. Systems with the priority classes, 1, 2 and 3 are analyzed, and the effect of the number of priority classes is examined.

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CRP-CMAC: A Priority-Differentiated Cooperative MAC Protocol with Contention Resolution for Multihop Wireless Networks

  • Li, Yayan;Liu, Kai;Liu, Feng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권11호
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    • pp.2636-2656
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    • 2013
  • To improve the cooperative efficiency of node cooperation and multiple access performance for multihop wireless networks, a priority-differentiated cooperative medium access control protocol with contention resolution (CRP-CMAC) is proposed. In the protocol, the helper selection process is divided into the priority differentiation phase and the contention resolution phase for the helpers with the same priority. A higher priority helper can choose an earlier minislot in the priority differentiation phase to send a busy tone. As a result, the protocol promptly selects all the highest priority helpers. The contention resolution phase of the same priority helpers consists of k round contention resolution procedures. The helpers that had sent the first busy tone and are now sending the longest busy tone can continue to the next round, and then the other helpers that sense the busy tone withdraw from the contention. Therefore, it can select the unique best helper from the highest priority helpers with high probability. A packet piggyback mechanism is also adopted to make the high data rate helper with packet to send transmit its data packets to its recipient without reservation. It can significantly decrease the reservation overhead and effectively improve the cooperation efficiency and channel utilization. Simulation results show that the maximum throughput of CRP-CMAC is 74%, 36.1% and 15% higher than those of the 802.11 DCF, CoopMACA and 2rcMAC protocols in a wireless local area network (WLAN) environment, and 82.6%, 37.6% and 46.3% higher in an ad hoc network environment, respectively.

정보화 투자사업의 평가기준 설정 및 우선순위 결정에 관한 연구 (A Research for the Setup of Evaluation Standards and the Decision of an Investment Priority of Information and Communication Enterprises of the Government)

  • 송의근;김성언
    • 한국정보시스템학회지:정보시스템연구
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    • 제16권3호
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    • pp.91-108
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    • 2007
  • To decide a reasonable investment priority of public enterprises, it is required to have an efficient evaluation standard. However, without having a standard, a budget for those enterprises has been allocated. In this research, for the efficient and reasonable budget allocation, it is discussed how to decide investment priority of information and communication enterprises of the government. In order to examine possible alternatives of the investment priority of information and communication enterprises of the government, seventeen enterprises were chosen from the enterprises of Ministry of Information and Communication. Public benefit, economic benefit, technology, politics, and step-up increase of budget were set up as evaluation standards and 16 specific standards were set up as subordinates. A hierarchical decision model was designed and analyzed by using AHP.

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통신망에서의 동적우선도큐잉에 관한 연구 (A Study on the Queueing with Dynamic Priority in Communication Network)

  • 이재호;송영재
    • 한국통신학회논문지
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    • 제12권2호
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    • pp.92-101
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    • 1987
  • 통신망에 입력하는 메시지는 그 메시지에 부과되는 우선도에 의하셔 큐잉(Queueing)되며 큐(Queue)에서의 우선도는 여러가지 방법으로 취급되어진다. 이 연구는 메시지 처리의 한 방법인 동적 우선도(dynamic priority)에 관한 것으로 메시지의 평균 대기 시간에 관한 해석이다. 큐에서의 메시지의 대기 시간에 따라 우선도가 변하는 동적 우선도의 가변성은 그 메시지가 초기 우선도(initial priority)를 가지고 입력되는 경우가 초기우선도를 가지지 않는 경우 달라지는 것으로 특히 그 차이점을 고찰하였다.

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Assured Forwarding 클래스를 위한 동적 엄격 패킷 폐기 메커니즘 (Dynamic and Strict Packet Dropping Mechanism for Assured Forwarding Classes)

  • 김수연;이호균;김철범
    • 한국정보처리학회논문지
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    • 제6권11S호
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    • pp.3251-3259
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    • 1999
  • In this paper, we present a new mechanism applying more strict priority than RIO mechanism proposed as a drop precedence policy of AF classes in differentiated services. In this mechanism, applying strict priority to drop precedence policy, we get better performance on priority level. Simulation results indicate that the proposed mechanism may provide more efficient and more strict priority transmissions as compared to RIO regardless of traffic load.

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효율적인 패킷 분류를 위한 계층 우선순위 트라이 (Hierarchical Priority Trie for Efficient Packet Classification)

  • 추하늘;임혜숙
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2007년도 하계종합학술대회 논문집
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    • pp.15-16
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    • 2007
  • In order to provide value-added services, next generation routers should perform packet classification for each incoming packet at wire-speed. In this paper, we proposed hierarchical priority trio (Hptrie) for packet classification. The proposed scheme improves the search performance and the memory requirement by replacing empty internal nodes in ordinary hierarchical trio with priority nodes which are the nodes including the highest priority rule among sub-trie nodes.

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실시간 서버 시스템에서 우선 순위 반전현상을 감소하기 위한 모델 (A Model for Reducing Priority Inversion in Real Time Server System)

  • 최대수;임종규;구용완
    • 한국정보처리학회논문지
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    • 제6권11호
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    • pp.3131-3139
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    • 1999
  • Satisfying the rigid timing requirements of various real-time activities in real-time systems often requires some special methods to tune the systems run-time behaviors. Unbounded blocking can be caused when a high priority activity cannot preempt a low priority activity. In such situation, it is said that a priority inversion has occurred. The priority inversion is one of the problems which may prevent threads from meeting the deadlines in the real-time systems. It is difficult to remove such priority inversion problems in the kernel at the same time to bound the worst case blocking time for the threads. A thread is a piece of executable code which has access to data and stack. In this paper, a new real-time systems. It is difficult to remove such priority inversion problems in the kernel at the same time to bound the worst case blocking time for the threads. A threads is a piece of executable code which has access to data and stack. In this paper, a new real-time server model, which minimizes the duration of priority inversion, is proposed to reduce the priority inversion problem. The proposed server model provides a framework for building a better server structure, which can not only minimize the duration of the priority inversion, but also reduce the deadline miss ratio of higher priority threads.

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